Polarization stable low threshold current single fundamental mode VCSELs

Abstract

The characteristics of polarization stable microstructure vertical-cavity surface-emitting lasers (PS-MS-VCSELs) with low threshold current and single fundamental mode (SFM) operation were theoretically and experimentally investigated. Elliptical air hole photonic crystal (EPC) structure was incorporated in the top mirror of the MS-VCSELs to realize single fundamental mode operation. By controlling the mode loss difference among the two orthogonal modes, the fundamental mode and other high order modes of the MS-VCSELs, through suitable oxide aperture shape and EPC parameters, a high performance PS-MS-VCSEL is achieved with output power of 1.6 mW, low threshold current of 0.8 mA as well as more than 20 dB orthogonal polarization suppression ratio (OPSR).